Yes. Before the end of the Bracero Program, Mexicans would visit their American relatives in the North, but rarely stayed. I can remember that in the early 1960's, here in California, illegal immigration was not even an issue. By the 1970's, the Immigration Service was raiding businesses in Los Angeles as a result of the '65 Immigration Act.
That's an astoundingly absurd assertion.
No, this statement of yours is absurd. To wit: "Especially since they were wandering into lands that used to belong to them?". That makes it right in your mind, does it? It would seem that you have a curious way of interpreting the law or the concept of a sovereign nation that suits your convenience. I wonder how the island country of Taiwan would fare if it had the amount of immigration from the Chinese mainland that the US has from Mexico? After all, Taiwan used to belong to China, therefore, the Red Chinese have the right to "wander" onto lands that "used (?) to belong to them". N'est ce pas?
All I can say based on reading your posts, especially your last two, is that you ought to be really really careful tossing around the word "ignorant."
e.g., "illegal immegration was extremely rare before 1965".
Moreover, none of your examples regarding Taiwan have any relevance whatsoever regarding the question of whether our tradition and law allows a child born in the U.S. to be considered a citizen. Yet you keep gnawing at them like a dog on a rubber bone. Nor have you been able to find a single case where anyone having been born in the U.S. has been legally denied a claim to citezenship since the 14th Amendment.
You simply have no argument other than to say you don't like the current situation. But that was never the point. You've run completely out of ammo and have lost the debate.